ATP5PO levels regulate enteric nervous system development in zebrafish, linking Hirschsprung disease to Down Syndrome

Hirschsprung disease (HSCR) is a complex genetic disorder characterized by the absence of enteric nervous system (ENS) in the distal region of the intestine. Down Syndrome (DS) patients have a >50-fold higher risk of developing HSCR than the general population, suggesting that overexpression of human chromosome 21 (Hsa21) genes contribute to HSCR etiology. However, identification of responsible genes remains challenging. Here, we describe a genetic screening of potential candidate genes located on Hsa21, using the zebrafish. Candidate genes were located in the DS-HSCR susceptibility region, expressed in the human intestine, were known potential biomarkers for DS prenatal diagnosis, and were present in the zebrafish genome. With this approach, four genes were selected: RCAN1, ITSN1, ATP5PO and SUMO3. However, only overexpression of ATP5PO, coding for a component of the mitochondrial ATPase, led to significant reduction of ENS cells. Paradoxically, in vitro studies showed that overexpression of ATP5PO led to a reduction of ATP5PO protein levels. Impaired neuronal differentiation and reduced mitochondrial ATP production, were also detected in vitro, after overexpression of ATP5PO in a neuroblastoma cell line. Finally, epistasis was observed between ATP5PO and ret, the most important HSCR gene. Taken together, our results identify ATP5PO as the gene responsible for the increased risk of HSCR in DS patients in particular if RET variants are also present, and show that a balanced expression of ATP5PO is required for normal ENS development.

Boosting hydrogen production of a MOF-based multicomponent photocatalyst with clean interface via facile one-pot electrosynthesis

Hydrogen production from photocatalysis via the usage of multicomponent photocatalysts represents a promising pathway for carbon peaking and carbon neutrality, owing to their structural advantages in dealing with the three crucial processes in photocatalysis, namely, light harvesting, charge transfer, and surface redox reactions. We demonstrate the fabrication of a MOF-based multicomponent photocatalyst, denoted as semiconductor/MOF/cocatalyst, by a one-pot electrochemical synthetic route. The as-fabricated multicomponent photocatalyst has a clean interface among the components, leading to close connections that contribute to high-quality heterojunction and facilitate photogenerated charge transfer and separation, thereby the efficient hydrogen evolution. The hydrogen production rate of the resultant ZrO2 /Zr-MOF/Pt is 1327 μmol ⋅ g-1  ⋅ h-1 , which is much higher than that of ZrO2 /Zr-MOF (15 μmol ⋅ g-1  ⋅ h-1 ) and pure Zr-MOF (10.1 μmol ⋅ g-1  ⋅ h-1 ), as well as the photodeposited-Pt products ZrO2 /Zr-MOF/PtPD (287 μmol ⋅ g-1  ⋅ h-1 ) and Zr-MOF/PtPD (192 μmol ⋅ g-1  ⋅ h-1 ) obtained by the step-wise synthetic approach. The work gives a good inspiration for the rational design and construction of MOF-based multicomponent photocatalysts through the one-pot electrosynthesis.

Natural products modulate NLRP3 in ulcerative colitis

Ulcerative colitis (UC) is a clinically common, progressive, devastating, chronic inflammatory disease of the intestine that is recurrent and difficult to treat. Nod-like receptor protein 3 (NLRP3) is a protein complex composed of multiple proteins whose formation activates cysteine aspartate protease-1 (caspase-1) to induce the maturation and secretion of inflammatory mediators such as interleukin (IL)-1β and IL-18, promoting the development of inflammatory responses. Recent studies have shown that NLRP3 is associated with UC susceptibility, and that it maintains a stable intestinal environment by responding to a wide range of pathogenic microorganisms. The mainstay of treatment for UC is to control inflammation and relieve symptoms. Despite a certain curative effect, there are problems such as easy recurrence after drug withdrawal and many side effects associated with long-term medication. NLRP3 serves as a core link in the inflammatory response. If the relationship between NLRP3 and gut microbes and inflammation-associated factors can be analyzed concerning its related inflammatory signaling pathways, its expression status as well as specific mechanism in the course of IBD can be elucidated and further considered for clinical diagnosis and treatment of IBD, it is expected that the development of lead compounds targeting the NLRP3 inflammasome can be developed for the treatment of IBD. Research into the prevention and treatment of UC, which has become a hotbed of research in recent years, has shown that natural products are rich in therapeutic means, and multi-targets, with fewer adverse effects. Natural products have shown promise in treating UC in numerous basic and clinical trials over the past few years. This paper describes the regulatory role of the NLRP3 inflammasome in UC and the mechanism of recent natural products targeting NLRP3 against UC, which provides a reference for the clinical treatment of this disease.

The gut microbes in inflammatory bowel disease: Future novel target option for pharmacotherapy

Gut microbes constitute the main microbiota in the human body, which can regulate biological processes such as immunity, cell proliferation, and differentiation, hence playing a specific function in intestinal diseases. In recent years, gut microbes have become a research hotspot in the pharmaceutical field. Because of their enormous number, diversity, and functional complexity, gut microbes have essential functions in the development of many digestive diseases. Inflammatory bowel disease (IBD) is a chronic non-specific inflammatory disease with a complex etiology, the exact cause and pathogenesis are unclear. There are no medicines that can cure IBD, and more research on therapeutic drugs is urgently needed. It has been reported that gut microbes play a critical role in pathogenesis, and there is a tight and complex association between gut microbes and IBD. The dysregulation of gut microbes may be a predisposing factor for IBD, and at the same time, IBD may exacerbate gut microbes' disorders, but the mechanism of interaction between the two is still not well defined. The study of the relationship between gut microbes and IBD is not only important to elucidate the pathogenesis but also has a positive effect on the treatment based on the regimen of regulating gut microbes. This review describes the latest research progress on the functions of gut microbes and their relationship with IBD, which can provide reference and assistance for further research. It may provide a theoretical basis for the application of probiotics, fecal microbiota transplantation, and other therapeutic methods to regulate gut microbes in IBD.

[Establishment and preliminary application of organoids in ovarian cancer]

Objective: To explore the establishment and application of ovarian cancer organoids. Methods: Fresh ovarian tumor tissues, obtaining from patients underwent surgery in the First Affiliated Hospital of Nanjing Medical University between October 2021 and March 2022, were collected, enzymatic degraded, digested, and embedded into matrigel to establish organoids. A total of 32 ovarian cancer samples were collected. Hematoxylin eosin (HE) staining and immunofluorescence (IF) procedure were used to verify the morphological structure of organoids and their expression of molecular markers. 3D cyto-live or dead assay was used to detecte the live or dead cells in organoids. Carboplatin with a concentration ranging from 5 to 80 μmol/L (5, 10, 20, 40, 80 μmol/L) was added to organoids to calculate the 50% inhibitory concentration (IC₅₀) in different organoids. Results: (1) Organoids from a total of 32 patients were established, of which 18 cases could be passaged stably in the long term in vitro, while 14 could be passaged in the short time. The average amplification time of long-term passage in vitro was over 3 months, and the longest reached 9 months. (2) In HE staining, significant nuclei atypia and local micropapillary structures were observed in organoids. IF staining revealed that ovarian cancer organoids expressed molecular markers similar to primary tumor tissues, such as Pan cytokeratin (Pan-CK), p53, paired box gene 8 (PAX8), and Wilms tumor gene 1 (WT1). (3) In 3D cyto-live or dead assay, a large number of apoptotic cells were observed inside and around the organoids after added carboplatin. The sensitivity to carboplatin varied in 18 organoids could amplify in the long term, with an average IC₅₀ of (29.5±15.8) μmol/L. Moreover, IC₅₀ values of 4 organoids derived from patients received neoadjuvant chemotherapy were much higher than the 14 organoids which did not received neoadjuvant chemotherapy [(48.7±11.3) μmol/L vs (24.0±12.1) μmol/L; t=3.429, P=0.022]. Conclusions: Organoids recapitulate ovarian cancers in vitro and could be stably passaged. Organoids derived from patients received neoadjuvant chemotherapy have higher resistance to carboplatin.

Room-Temperature High-Performance Thermoelectric Bi0.6 Sb0.4 Te: Elimination of Detrimental Band Inversion in BiTe

Room-temperature thermoelectric materials are the key to miniaturizing refrigeration equipment and have great scientific and social implications, yet their application is hindered by their extreme scarcity. BiTe exhibiting strong spin-orbit coupling peaks ZT at 600 K. Herein, we discover the synergy effect of Sb doping in BiTe that eliminates the detrimental band inversion and leads to an overlap of conduction band (CB) and valence band that significantly increases the S from 33 to 124 μV K^-1 . In addition, this effect enhances the μ from 58 to 92 cm²  V^-1  s^-1 owing to the sharp increase in the CB slope along the Γ-A in the first Brillouin zone. Furthermore, Sb doping increases the anharmonicity, shortens the phonon lifetime and lowers κ_lat . Finally, Se/Sb codoping further optimizes the ZT to 0.6 at 300 K, suggesting that Bi_0.6 Sb_0.4 Te_1-y Se_y is a potential room-temperature TE material.

[Six cases of acute toilet cleaners]

The oral toilet cleaners poisoning can result in devastating gastrointestinal tract injuries with the risk of perforation and/or hemorrhage, and sometimes potentially fatal systemic complications and sequelas. It should be given positive treatment. In this paper, six cases of acute toilet cleaners poisoning were analyzed, and the clinical characteristics and treatment effect were summarized, so as to improve the understanding, diagnosis and treatment level of the disease.

Risk factors for pulmonary embolism in patients with COVID-19: a systemic review and meta-analysis

PURPOSE

To detect the risk factors for pulmonary embolism (PE) in patients with COVID-19.

METHODS

Studies were searched for in PubMed, Cochrane Library, Web of Science, and EMBASE. Two authors independently screened articles and extracted data. The data were pooled by meta-analysis and three subgroup analyses were performed.

RESULTS

Of the 2210 articles identified, 27 studies were included. Pooled analysis suggested that males (odds ratio (OR) 1.49, 95% confidence interval (CI) 1.26-1.75, P = 0.000), obesity (OR 1.37, 95% CI 1.03-1.82, P = 0.033), mechanical ventilation (OR 3.34, 95% CI 1.90-5.86, P = 0.000), severe parenchymal abnormalities (OR 1.92, 95% CI 1.43-2.58, P = 0.000), ICU admission (OR 2.44, 95% CI 1.48-4.03, P = 0.000), and elevated D-dimer and white blood cell values (at two time points: hospital admission or closest to computed tomography pulmonary angiography) (P = 0.000) correlated with a risk for PE occurrence in COVID-19 patients. However, age and common comorbidities had no association with PE occurrence. Computed tomography pulmonary angiography, unclear-ratio/low-ratio, and hospitalization subgroups had consistent risk factors with all studies; however, other subgroups had fewer risk factors for PE.

CONCLUSIONS

Risk factors for PE in COVID-19 were different from the classic risk factors for PE and are likely to differ in diverse study populations.

[Oncologic outcomes of early stage cervical cancer performed operation by different laparoscopic surgical procedures: analysis of clinical data from mutiple centers]

Objective: To evaluate the oncologic outcomes of different laparoscopic radical hysterectomy. Methods: From January 2011 to December 2014, the laparoscopic operation cases of cervical cancer at stage Ⅰb1, Ⅰb2, Ⅱa1 and Ⅱa2, including the histologic subtypes of squamous-cell carcinoma, adenocarcinoma and adenosquamous carcinoma, were collected in five clinical centers. The data were divided into two groups according to the surgical procedures, that is, modified laparoscopic-vaginal radical hysterectomy (mLVRH) and total laparoscopic radical hysterectomy (TLRH). The overall survival rate (OS), disease-free survival rate (DFS) at 5 years were retrospectively analyzed in this study. Results: There were 674 cases in total, including 377 cases of mLVRH, 297 cases of TLRH. (1) The OS at 5 years: the mLVRH was 96.1% and the TLRH was 92.0%, and the mLVRH was higher than that of TLRH （P=0.010）. Stratify analysis， including stage of disease （Ⅰb1 and Ⅱa1）， histologic subtypes （squamous-cell carcinoma, adenocarcinoma）， lymph node metastasis， revealed that, ① Stage of disease: in stage Ⅰb1, the OS at five years of mLVRH was higher than that in TLRH group （98.6% vs 93.6%, P=0.012）. In stage Ⅱa1, there was significant difference between the two groups, the OS at five years of mLVRH and TLRH were 93.6% and 77.6% （P=0.007）. ② Histologic subtypes: for the OS at five years of squamous-cell carcinoma, mLVRH and TLRH were 96.1% and 92.3%, and there was significant difference （P=0.046）； for adenocarcinoma, the OS at five years were 91.0% and 88.6%， and there was no difference between two groups （P=0.230）. ③ Lymph node metastasis： the mLVRH and TLRH with lymph node metastasis, the OS at five years were 98.6% and 96.4%; the mLVRH and TLRH without lymph node metastasis, the OS at five years were 89.3% and 80.8%. There were no significant differences between the two groups,respectively (P=0.156， P=0.093）. (2) The DFS at 5 years: there was no significant difference between mLVRH and TLRH (94.1% vs 90.9%, P=0.220). Stratify analysis for stage of disease, the mLVRH group was higher than that in the TLRH group in stage Ⅰb1 (97.0% vs 92.8%, P=0.039). However, for stage Ⅱa1, there was no significant difference between mLVRH and TLRH group （88.2% vs 75.8%, P=0.074）. Conclusions: The results of this retrospective study indicated that different laparoscopy surgical procedures had diverse oncologic outcomes. The OS at 5 years of the mLVRH is superior to the TLRH. The DFS at 5 years in Ⅰb1 stage, the mLVRH is higher than the TLRH. Therefore, the modified laparoscopy is still an alternative surgery for early cervical cancer patients when following the principle of no-tumor-exposure.

[The attentional bias of emotion in medical workers of emergency department in one hospital and it's relationship with mood state]

Objective: To study the characteristics of attentional bias to emotional stimulus in medical workers of emergency department and explore the relationship between the emotional Stroop effect and mood states, thus providing a reference to the assessment and intervention of emergency medical workers' mental health. Methods: Two kinds of emotional Stroop tasks with words and pictures and the Profile of Mood States (POMS) were administered to thirty-six medical workers of emergency department and thirty-six medical workers of other departments. Results: The reaction time to negative and positive words and pictures were all higher than the reaction time to neutral stimulus, thus showing the significant Stroop effect in medical workers. The Stroop effect to negative emotional stimulus in medical workers of emergency department was significantly smaller than that in medical workers of other departments, while the difference of Stroop effect to positive stimulus was not significant between the two groups. Correlation analyses revealed that the correlations between Stroop effect size to positive pictures and tension and angry of POMS were all negatively significant (r value was -0.314 and -0.330 respectively) , and the correlation between Stroop effect size to negative pictures and fatigue was negatively significant (r=-0.303) . Conclusions: There is a significant emotional Stroop effect in medical workers. Although the ability of anti-interference to emotional stimulus in medical workers of emergency department was better than medical workers of the other departments, the long-term avoidance to negative emotional stimulus was still has a negative effect on the mood states of individuals.

Finite-temperature scaling of trace distance discord near criticality in spin diamond structure

In this work we explore the quantum correlation quantified by trace distance discord as a measure to analyze the quantum critical behaviors in the Ising-XXZ diamond structure at finite temperatures. It is found that the first-order derivative of the trace distance discord exhibits a maximum around the critical point at finite temperatures. By analyzing the finite-temperature scaling behavior, we show that such a quantum correlation can detect exactly the quantum phase transitions from the entan-gled state in ferrimagnetic phase to an unentangled state in ferrimagnetic phase or to an unentangled state in ferromagnetic phase. The results also indicate that the above two kinds of transitions can be distinguished by the different finite-temperature scaling behaviors. Moreover, we find that the trace distance discord, in contrast to other typical quantum correlations (e.g., concurrence, quantum discord and Hellinger distance), may be more reliable to exactly spotlight the critical points of this model at finite temperatures under certain situations.

Microsatellite markers reveal genetic divergence among wild and cultured populations of Chinese sucker Myxocyprinus asiaticus

Studies of genetic diversity and genetic population structure are critical for the conservation and management of endangered species. The Chinese sucker Myxocyprinus asiaticus is a vulnerable monotypic species in China, which is at a risk of decline owing to fluctuations in effective population size and other demographic and environmental factors. We screened 11 microsatellite loci in 214 individuals to assess genetic differentiation in both wild and cultured populations. The single extant wild population had a higher number of alleles (13) than the cultured populations (average 7.3). High levels of genetic diversity, expressed as observed and expected heterozygosity (HO = 0.771, HE = 0.748, respectively), were found in both wild and cultured populations. We also report significant differentiation among wild and cultured populations (global FST = 0.023, P < 0.001). Both STRUCTURE analysis and neighbor-joining tree revealed three moderately divergent primary genetic clusters: the wild Yangtze population and the Sichuan population were each identified as an individual cluster, with the remaining populations clustered together. Twenty-two samples collected from the Yangtze River were assigned to the cultured population, demonstrating the efficacy of artificial propagation to avoid drastic reduction in the population size of M. asiaticus. These genetic data support the endangered status of the M. asiaticus and have implications for conservation management planning.

Utilization of International Association of Diabetes and Pregnancy Study Groups criteria vs. a two-step approach to screening for gestational diabetes mellitus in Chinese women with twin pregnancies

AIM

To evaluate prevalence and pregnancy outcomes using the International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria and screening protocol vs. a standard two-step screening approach for gestational diabetes mellitus in Chinese twin pregnancies.

METHODS

A retrospective cohort study for pregnancies during 2007-2013 was performed in a tertiary hospital in Shanghai, China. Data were abstracted from the medical records of twin pregnancies delivered at the hospital. During the period 2007-2011, this hospital used a two-step approach with a 50 g screening with a cut-off value of ≥ 7.8 mmol/l followed by a 100 g diagnostic oral glucose tolerance test (OGTT) utilizing Carpenter-Coustan criteria. In 2012-2013, the hospital switched to the IADPSG protocol of universal 75 g OGTT.

RESULTS

Among 1461 twin pregnancies, 643 were screened utilizing IADPSG criteria and 818 using the two-step protocol. Gestational diabetes mellitus was diagnosed more frequently in the IADPSG group than in the two-step group [20.4% and 7.0%, respectively; adjusted odds ratio (aOR) = 3.22; 95% confidence interval (CI) = 2.30-4.52]. During the IADPSG period, the incidence of pre-eclampsia was 38% lower in non-gestational diabetes mellitus affected pregnancies compared with the two-step period (aOR = 0.62; 95% CI = 0.44-0.87). We observed no significant differences in most perinatal outcomes between the two groups.

CONCLUSION

Compared with a standard two-step approach to screening and diagnosis, the IADPSG screening method resulted in a three-fold increase in the incidence of gestational diabetes mellitus in twin pregnancies, with a 38% lower risk of pre-eclampsia but no significant difference in most perinatal outcomes in non-gestational diabetes mellitus affected pregnancies.

Agonist of farnesoid X receptor protects against bile acid induced damage and oxidative stress in mouse placenta--a study on maternal cholestasis model

INTRODUCTION

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific disorder, which is characterized by raised serum bile acid level and potential adverse fetal outcome. Farnesoid X receptor (FXR), also known as a bile acid receptor, was found to be expressed in placenta with low level. Whether activation of FXR by specific agonists could regulate the pathogenesis of ICP is still unclear.

METHODS

A model of maternal cholestasis was induced by administration of 17α-ethynylestradiol (E2) in pregnant mice for 6 days. We explored the regulatory effect of WAY-362450 (W450), a highly selective and potent FXR agonist on placenta.

RESULTS

In this study, we demonstrated that administration of E2 increased bile acid levels in mouse serum, liver and amniotic fluid. Bile acid levels were significantly decreased after W450 treatment. W450 protected against the impairment of placentas induced by E2, including severe intracellular edema and apoptosis of trophoblasts. Moreover, W450 significantly induced the expressions of FXR target bile acid transport gene ATP-binding cassette, sub-family B (MDR/TAP), member 11 (Abcb11;Bsep) in placenta. W450 could also attenuate placental oxidative stress and increase the expressions of antioxidant enzymes Prdx1 and Prdx3.

DISCUSSION AND CONCLUSION

In conclusion, our data demonstrated that FXR agonist W450 modulated bile acid balance and protected against placental oxidative stress. Thus, our results support that potent FXR agonists might represent promising drugs for the treatment of ICP.

Single-walled carbon nanotube induction of rat aortic endothelial cell apoptosis: Reactive oxygen species are involved in the mitochondrial pathway

The use of nano-sized materials offers exciting new options in technical and medical applications. Single-walled carbon nanotubes are emerging as technologically important in different industries. However, adverse effects on cells have been reported and this may limit their use. We previously found that 200μg/mL of single-walled carbon nanotubes induce apoptosis in rat aorta endothelial cells. The current study aimed to determine the signaling pathway involved in this process. We found that reactive oxygen species generation was involved in activation of the mitochondria-dependent apoptotic pathway. The finding of apoptosis was supported by a number of morphological and biochemical hallmarks, including chromatin condensation, internucleosomal DNA fragmentation, and caspase-3 activation. In conclusion, our results demonstrate that single-walled carbon nanotubes induce apoptosis in rat aorta endothelial cells and that reactive oxygen species are involved in the mitochondrial pathway.

Serum amyloid A is elevated in the serum of lung cancer patients with poor prognosis

Background:

Lung cancer is known as the top cancer killer in most developed countries. However, there is currently no promising diagnostic or prognostic biomarker for lung cancer. This study aims to discover non-invasive differential markers in the serum of lung cancer patients, to determine the protein identity of the candidate biomarker(s), and to investigate any clinical implication of the biomarker(s) concerned.

Methods:

Blood specimens were collected from 154 pre-operative patients with lung cancer and 35 healthy blood donors with no evidence of lung cancer. Fractionated serum samples were processed by surface-enhanced laser desorption/ionisation time-of-flight mass spectrometry (MS). Candidate biomarker was identified using sodium dodecyl sulphate polyacrylamide gel electrophoresis and tryptic digestion followed by tandem MS fragmentation analysis, which was subsequently validated with immunoassay.

Results:

A differential protein with m/z 11.6 kDa was detected and identified as an isoform of human serum amyloid A (SAA). It was significantly increased by 1822% in lung cancer patients when compared with the healthy controls, which gave an area under the receiver operator characteristic curve of 0.88. In addition, the protein was also significantly elevated by 77% in lung cancer patients with survival <5 years when compared with patients with survival ⩾5 years.

Conclusion:

There are several functions of the SAA protein, described in the context of inflammation, that are compatible with the mechanism of tumour invasion and metastasis. Our study not only detected increased SAA level in the serum of lung cancer patients but also identified that elevated SAA level may be a non-invasive biomarker useful for the prediction of lung cancer prognosis.

The use of single chain Fv as targeting agents for immunoliposomes: an update on immunoliposomal drugs for cancer treatment

IMPORTANCE OF THE FIELD

Targeted liposomal drugs represent the next evolution of liposomal drug delivery in cancer treatment. In various preclinical cancer models, antibody-targeted PEGylated liposomal drugs have demonstrated superior therapeutic effects over their non-targeted counterparts. Single chain Fv (scFv) has gained popularity in recent years as the targeting agent of choice over traditional targeting agents such as monoclonal antibodies (mAb) and antibody fragments (e.g., Fab').

AREAS COVERED IN THIS REVIEW

This review is focused mainly on advances in scFv-targeted liposomal drug delivery for the treatment of cancers, based on a survey of the recent literature, and on experiments done in a murine model of human B-lymphoma, using anti-CD19 targeted liposomes targeted with whole mAb, Fab' fragments and scFv fragments.

WHAT THE READER WILL GAIN

This review examines the recent advances in PEGylated immunoliposomal drug delivery, focusing on scFv fragments as targeting agents, in comparison with Fab' and mAb.

TAKE HOME MESSAGE

For clinical development, scFv are potentially preferred targeting agents for PEGylated liposomes over mAb and Fab', owing to factors such as decreased immunogenicity, and pharmacokinetics/biodistribution profiles that are similar to non-targeted PEGylated (Stealth) liposomes.

Structure, castability and mechanical properties of commercially pure and alloyed titanium cast in graphite mould

This report is a study of structure, castability, mechanical properties as well as corrosion behaviour of titanium doped with up to 5 weight percentage (wt%) of a series of alloy elements, including Ta, Mo, Nb, Hf, Zr, Sn, Bi and Ag. The results indicate that, with addition of 1 wt% alloy element, Bi and Mo were most effective in enhancing the castability of titanium. With more alloy elements added, the castability values of most alloys more or less decreased. Except Ti-Mo system, all Ti alloys with a fine acicular morphology had the same crystal structure (hcp) as that of c.p. Ti with a typical lath type morphology. When 3 wt% or more Mo was added, a finer orthorhombic alpha'' phase was formed. The microhardness and bending strength values of Ti alloys were all higher than those of c.p. Ti. Among all alloys, Ti-Mo system exhibited the highest hardness and strength level. For a certain alloy, the bending strength did not necessarily increase with its alloy content. Except Ti-5Zr and Ti-Mo alloys, the bending moduli of most alloy systems were not much different from that of c.p. Ti. All alloys showed an excellent resistance to corrosion in Hanks' solution at 37 degrees C.

Acute and sublethal toxicities of rotenone in juvenile rainbow trout (Oncorhynchus mykiss): swimming performance and oxygen consumption

Rotenone, a natural insecticide and piscicide, was shown to have an extremely small margin between no lethality (5.0 microg/L) and 100% mortality (6.6 microg/L) for static-renewal 96-hour toxicity tests with juvenile rainbow trout (Oncorhynchus mykiss). Dissolved organic carbon (DOC) at concentrations of 3.0 and 4.0 mg/L significantly increased the rotenone 96-hour LC(50) (median lethal concentration) from 5.80 microg/L (confidence interval (CI) 5.51 to 6.10) to 6.55 microg/L (CI 6.28 to 6.83) and 7.75 microg/L (CI 7.29 to 8.24), respectively, probably as a result of rotenone adsorption onto DOC, which decreased its bioavailability. Using concentrations of 0, 3.0, 4.0, and 5.0 microg/L rotenone and exposure periods of 2, 4, 6, 12, 16, 24, and 48 hours, the threshold concentration of rotenone for impairment of critical swimming performance (Ucrit) was 3.0 microg/L (P = 0.029), with no further impairment at higher concentrations and no time-dependent effect on Ucrit. Using continuous measures of oxygen uptake for 48 hours before and 48 hours during rotenone exposure (0, 1.5, 2.5, 3.0, and 3.5 microg/L), rotenone significantly decreased peak active oxygen uptake at all rotenone concentrations tested without affecting routine oxygen uptake. Fish were individually chased and then placed in rotenone concentrations of 0, 1.0, 3.0, 4.0, 5.0, and 6.0 microg/L to monitor initial postexercise oxygen uptake (Mo2Max) and excess postexercise oxygen consumption (EPOC) during a 40-minute recovery period. Rotenone significantly decreased Mo2Max (P = 0.002) after exposures to 4.0 and 5.0 microg/L, but not 6.0 microg/L, without affecting EPOC.

Clinical Role of Circulating Epstein-Barr Virus DNA as a Tumor Marker in Lymphoepithelioma-Like Carcinoma of the Lung

Nineteen Chinese patients with lymphoepithelioma-like carcinoma (LELC) of the lung were tested for Epstein-Barr virus (EBV) DNA in their serum samples by a quantitative polymerase chain reaction (PCR) technique. There was prospective serial monitoring of the serum in seven patients with advanced inoperable or relapsing disease. Five other patients at first diagnosis and two patients at relapse had only a single serum sample available. Serum samples were also taken from three other patients who had prior curative surgery and two patients with prolonged disease remission. Measurable levels of EBV DNA were detected in 11 of 12 patients with a pre-therapy serum sample and a clinically evident tumor. A low level of EBV DNA was also detectable in one of the two other patients whose first serum samples were obtained after some chemotherapy. There was no detectable EBV DNA in the five patients without evidence of tumor. The longitudinal serum EBV DNA profile of seven patients showed consistent correlation with response to therapy and clinical outcome. Patients with a pre-therapy serum EBV DNA >10,000 copies/mL had significantly inferior overall survival. This study suggests that circulating serum EBV DNA can be used as a tumor marker in the clinical management of patients with LELC of the lung.

Estimation of bacterial risk in extending the shelf life of PLT concentrates from 5 to 7 days

BACKGROUND

The use of bacterial culture to prevent bacterial contamination of blood components has renewed interest for extending the shelf life of PLT concentrates to 7 days after collection.

STUDY DESIGN AND METHODS

This study was therefore conducted to determine the residual risk of bacterial contamination in PLT concentrates at the end of 5 and 7 days after collection in a center where all PLT concentrates are routinely screened by taking samples on Day 2 for culture. PLT units with no growth after 48 hours were sampled a second time on Day 5 or Day 7 after collection, followed by inoculation into aerobic culture bottles. The inoculated bottles were then monitored for up to 7 days at 35 degrees C in an automatic monitoring and detection system.

RESULTS

During a 16-month study period, a total of 6020 PLT concentrates were tested 5 days (Group A, n=3010) and 7 days (Group B, n=3010) after collection. Four units in each group (0.133%) were found to be contaminated. In 6 units, bacteria were seen on direct Gram stain. In addition, 5 of the associated RBC units grew the same organisms on culture. The organisms include three coagulase-negative staphylococci and five Propionibacterium acnes. The positive rate of routine short-term bacterial culture was 0.035 percent during the same study period.

CONCLUSION

Despite routine short-term bacterial culture, a significant risk of bacterial contamination remains at 5 and 7 days after collection. For now, the shelf life of PLT concentrates should remain 5 days.

Paediatric stroke: case series

Five cases of paediatric stroke are reported. Two patients presented with idiopathic stroke, another following vertebral artery dissection, one secondary to Moyamoya disease, and one patient with the syndrome of mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes. The presentation, investigation, and management of paediatric stroke are discussed.

Remarkable application of serum EBV EBER-1 in monitoring response of nasopharyngeal cancer patients to salvage chemotherapy

Nineteen consecutive patients with metastatic or recurrent nasopharyngeal cancer (NPC) receiving combination chemotherapy were monitored for EBV DNA in their serum. EBV DNA (EBER-1) concentration in serum was measured before, during, and after chemotherapy. Thirteen patients had additional multiple prechemotherapy readings. There was a significant lead time from first detection of serum EBER-1 to clinical recurrence in 62% of patients by a mean of 17.4 weeks (range: 8-74.5 weeks; mean = 28.2 weeks if confined to the 8 patients with significant lead time). The median EBER-1 concentration was significantly higher in those with distant metastasis as compared to those with loco-regional recurrence only (17,468 vs. 684 pg/mL serum; p = 0.046, Mann-Whitney U test). Among the 13 patients who responded to chemotherapy, 4 exhibited clinical complete remission (CR) who were only found in the group with EBER-1 DNA drop to background level, while the magnitude of EBER-1 drop did not discriminate partial remission (PR) and stable disease (SD) patients clearly. Subsequent profile of EBER-1 DNA showed concordance with clinical course of either continuous remission or later progression. EBER-1 DNA in serum can become a useful adjunctive surrogate marker to monitor chemotherapeutic response in NPC patients with distant metastasis or advanced local recurrence.

Epidemiology of headache in Hong Kong primary-level schoolchildren: questionnaire study

OBJECTIVE

To collect and analyse epidemiological data on childhood headache in the Hong Kong community.

DESIGN

Questionnaire study.

SETTING

Three primary schools, Hong Kong.

PARTICIPANTS

Two thousand, one hundred and twenty pupils from 2156 replied to the questionnaire survey. One hundred and twenty-four pupils who were identified to have suspected recurrent headache were invited to a follow-up medical consultation.

MAIN OUTCOME MEASURES

Age-groups and prevalence of tension-type and migraine headache, using the diagnostic criteria of the International Headache Society.

RESULTS

The overall prevalence of headache in the 2120 respondents was 2.8%. The prevalence of tension-type headache, migraine, probable migraine, and unclassified headache were 1.2%, 0.5%, 0.7%, and 0.5%, respectively. The age-specific prevalence of headache from the age of 6 to 13 years showed a steadily increasing trend from childhood to the early teens.

CONCLUSION

Headache is a common complaint for children, although it may be underrecognised. Further study will be beneficial for providing better management of headache in this population.

Surgery for intractable epilepsy in a 14-year-old girl

We report on a 14-year-old girl who presented with a 2-year history of simple and complex partial seizures with secondary generalisation. Monotherapy using carbamazepine and combination therapy using carbamazepine and gabapentin had been tried within the 2 years before presentation. Seizure control, however, was poor. Magnetic resonance imaging showed structural abnormalities over the right occipital and temporal lobes. Continuous scalp video electroencephalography was performed over 4 days, during which six clinical seizures were associated with electroencephalography changes at the right occipital and temporal lobes. Invasive intracranial video electroencephalography identified a focus at the right occipital lobe, a focus at the right temporal lobe that spread rapidly to the right parietal lobe, and an irritative zone over the posterior part of the right frontal lobe. Functional mapping delineated the motor and sensory cortices. Right temporal lobectomy, right occipitoparietal cortical excision, and multiple subpial transections of the posterior part of the right frontal lobe were performed. For 16 months after the surgery, the patient has been seizure-free while receiving drug treatment, and the only complication reported has been a segmental loss of the left visual field.

[Low-dose of processed rhubarb in preventing pregnancy induced hypertension]

A prospective randomized double blind study with processed rhubarb (low dose of 0.75g/day) was carried out in pregnant women at risk of pregnancy induced hypertension (PIH). Rhubarb (140 cases) or placebo (125 cases) was given to women at risk of PIH consecutively from the 28th week of gestation till delivery, and another 68 pregnant women as control. Results showed that 5.7% of rhubarb treated women developed PIH, a rate substantially lower than the 20.8% of the placebo group (P < 0.01). After 9-10 weeks of treatment, the plasma fibronectin (Fn) level and Plasminogen activator inhibiter (PAI) value were found significantly lower (P < 0.05) in the rhubarb treated group than in the placebo. Antithrombin III (ATIII) level also decreased significantly less in the rhubarb group as compared with the placebo (P < 0.05). It indicated that low dose of processed rhubarb has a good prophylactic effect on PIH. The mechanism may be related with the inhibition of PAI activity, reduced Fn synthesis and decreased damage to vascular endothelium.

Comparative studies of water quality in two brackish ponds for shrimp cultivation in a salt marsh

Physical, chemical and microbiological characteristics of two 'keiwais' (brackish ponds built along the coastal area for shrimp cultivation) in the Mai Po Marshes, Hong Kong, were measured and compared. One keiwai, located closer to the domestic and agricultural areas, had lower shrimp production than the other. Physical, microbiological and most of the chemical parameters of two keiwais showed no significant difference, while the keiwai closer to the domestic and agricultural areas had higher biochemical oxygen demand (BOD5), and higher levels of phosphate (PO4(3-)-P) and cadmium (Cd2+). Results of the present study indicate that these keiwais were polluted by sewage discharged from nearby domestic, agricultural and industrial areas. The possibility that water received by the less polluted keiwai was purified by surrounding mangroves and sediments in the Mai Po Marshes is discussed.

[Low-dose aspirin preventing pregnancy induced hypertension]

A prospective randomized double-blind study was carried out in pregnant women with risk of pregnancy induced hypertension (PIH). Low dose Aspirin (50 mg/day) or placebo was given consecutively from the 28th weeks of gestation. The results have shown that 8% of the pregnant women in the aspirin treatment group had developed PIH, which was substantially lower than that in the control group (24%) (P less than 0.05). The ratio of TXB2/6-keto-PGF1 alpha increased significantly in the control group while it remained unchanged in treatment group. Increasing plasma fibronectin (Fn) and decreasing AT-III level were seen in the control group but no changes of these parameters in the treatment group. It was presumed that low dose aspirin may have prophylactic effect on PIH. The mechanism of aspirin may be the inhibition of TXA2 and Fn synthesis and decreased consumption of AT-III.